SWRCH22A钢自攻螺钉断裂失效分析与工艺改进  

Failure analysis and technological improvement of SWRCH22A steel self-tapping screw

作　　者：马志敖 杨青 王小琴 李政 MA Zhiao;YANG Qing;WANG Xiaoqin;LI Zheng(Chongqing SERES New Energy Vehicle Design Institute Co.,Ltd.,Chongqing 401331,China)

机构地区：[1]重庆赛力斯新能源汽车设计院有限公司,重庆401331

出　　处：《金属加工（热加工）》2024年第11期97-101,共5页MW Metal Forming

摘　　要：针对SWRCH22A钢自攻螺钉使用过程中发生断裂的原因进行探究,对断裂螺钉进行了化学成分分析、含氢量检测、硬度测试及金相分析。结果表明:断裂失效样品化学成分符合标准要求,含氢量满足设计要求,表面与心部硬度满足技术指标,但渗碳层深度超出了规定值。通过对失效样品断口形貌深入分析,局部断口形貌呈沿晶脆性断裂特征,与热处理工艺参数不当有关。优化改进了螺钉渗碳工艺并装车使用,试验效果良好。The cause of fracture of SWRCH22A steel self-tapping screw sample during use was explored.Chemical composition analysis,hydrogen content detection,hardness test and metallographic analysis were carried out on the broken screw.The results showed that the chemical composition of the sample met the standard requirements,the hydrogen content met the design requirements,and the surface and core hardness met the technical indicators.But the depth of the carburizing layer exceeds the specified value.Through the in-depth analysis of the fracture morphology of the sample,the local fracture morphology is characterized by intergranular brittle fracture,which is related to improper heat treatment parameters.The screw carburizing process was optimized and improved,and the experiment results were good.

关 键 词：SWRCH22A钢 自攻螺钉 失效分析 渗碳层 沿晶断裂 热处理工艺 

分 类 号：TG115[金属学及工艺—物理冶金] TG156.81[金属学及工艺—金属学]